Influence of prohexadione-calcium and paclobutrazol on growth, yield and mineral content of pear cv. Clapp’s favourite

Abstract

Present investigation was carried out to study the influence of growth retardants viz., prohexadione-calcium and paclobutrazol on mineral content of pear cv. ‘Clapp’s Favourite’ during the year 2015-2016. The experiment was laid out with thirteen treatments, replicated thrice on 12 year-old-pear tree with uniform vigor and health under uniform cultural practices. The treatment comprised of single and double spray of growth retardants i.e., prohexadione-calcium (100 ppm, 200 ppm and 300 ppm) and paclobutrazol (100 ppm, 200 ppm and 300 ppm). The first spray of these growth retardants was given at complete petal fall stage and second at four weeks after first spray. The orchard soil was moderately deep with good fertility status. Results revealed that both the growth retardants had showed a significant influence on the studied characters. The plants sprayed twice with prohexadione-calcium @ 200 ppm (T9S2) recorded minimum annual shoot extension growth of 16.92 cm and leaf area (22.20 cm2) alongwith increase in fruit yield (51.24 kg). Highest value for calcium (Ca) in leaves and fruits of pear (574.00 mg & 71.24 mg, respectively) was recorded when plants were sprayed twice with prohexadione-calcium at 300 ppm. Results also revealed that application of prohexadione-calcium application at 200 ppm sprayed twice (T9S2) resulted in significant increased in potassium content of the pear leaves and fruits i.e. 98.40 mg and 22.78 mg, respectively. However minimum value for potassium content was recorded in control (T1S0). Double spray of prohexadione-calcium @ 200 ppm was effective in reducing the annual extension growth, leaf area and increasing the fruit yield and calcium and potassium content in leaves and fruit.